Strathmore Postcards:
I've been loving these Strathmore brand watercolor postcards. They're 300 gsm, so they're relatively heavy bond and you can really glop on the gouache (though it's not a great method, admittedly).
Check them out here.
Princeton Brushes:
I started messing around with painting after buying one of these Chronicle Books paint-by-number kits. And while the brush sorta sucked and the acrylics weren't great quality, it was a ton of fun.
I've subsequently discovered the wonderful world of Princeton Paint Brushes, and have been using a number of different brushes from their Real Value (9100) series. Then, once I felt like I was actually getting better, I upgraded to a four-piece set of Princeton's Velvetouch brushes, and the difference was night and day. I still suck, but when I get better, I'll upgrade again, probably. But so far, I love Princeton brushes.
The Gouache:
I started out with a set of affordable Savoir Faire gouache tubes, and they were great to learn on. Once I'd burned through most of them, I gave myself a little upgrade to the Holbein Artists Gouache, and it's so much creamier and easier to mix. I really love this stuff.
While artists gouache has been great to work with, I've also recently been painting with Holbein Acrylic Gouache, which unlike the artists gouache, doesn't reactivate with water. This makes it a bit easier not to accidentally fudge-up a painting with an errant drip of water. The downside is that if I've messed something up using acrylic gouache, I can't as easily use water to clean up the mistake. So, it's a give-and-take, but I've been really happy with the Holbein Acrylic Gouache.
The Wet Palette:
My pal and neighbor Magan Ruthke is not only a mind-blowing artist but a real supporter of other artists, including idiots like me! She suggested I get a wet palette to save myself time and to keep me from wasting paint. It's been a game changer, and I've loved using this Nicpro wet palette, which is portable and great at keeping my paint soft so that I don't have to continually re-wet it (and thereby dillute it).
Cleanup:
I've been using Speedball Pink Soap and this wash tank system from MyLifeUNIT, which includes a nifty drying rack so that my brushes stay in good shape. So far, so good!
Storage:
Look, I know it's prescious, but it's also super useful. This Italian-made single layer steel toolbox is a good size for all of my paint, brushes, wet palette, rolls of masking tape, etc.
Miscellaneous:
A couple of things that have helped me get better and sharper are this Fiskars brand bone folder, which I use to seal the edges of the KIWIHUB watercolor masking tape that I bought at Artist and Craftsman Supply in Baltimore. When I'm done with a piece, I use a matte finish fixatif (another Magan Ruthke recommendation!) on each piece. I'm using this one.